1 /* 2 * Driver for USB ethernet port of Conexant CX82310-based ADSL routers 3 * Copyright (C) 2010 by Ondrej Zary 4 * some parts inspired by the cxacru driver 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/module.h> 21 #include <linux/netdevice.h> 22 #include <linux/etherdevice.h> 23 #include <linux/ethtool.h> 24 #include <linux/workqueue.h> 25 #include <linux/mii.h> 26 #include <linux/usb.h> 27 #include <linux/usb/usbnet.h> 28 29 enum cx82310_cmd { 30 CMD_START = 0x84, /* no effect? */ 31 CMD_STOP = 0x85, /* no effect? */ 32 CMD_GET_STATUS = 0x90, /* returns nothing? */ 33 CMD_GET_MAC_ADDR = 0x91, /* read MAC address */ 34 CMD_GET_LINK_STATUS = 0x92, /* not useful, link is always up */ 35 CMD_ETHERNET_MODE = 0x99, /* unknown, needed during init */ 36 }; 37 38 enum cx82310_status { 39 STATUS_UNDEFINED, 40 STATUS_SUCCESS, 41 STATUS_ERROR, 42 STATUS_UNSUPPORTED, 43 STATUS_UNIMPLEMENTED, 44 STATUS_PARAMETER_ERROR, 45 STATUS_DBG_LOOPBACK, 46 }; 47 48 #define CMD_PACKET_SIZE 64 49 #define CMD_TIMEOUT 100 50 #define CMD_REPLY_RETRY 5 51 52 #define CX82310_MTU 1514 53 #define CMD_EP 0x01 54 55 /* 56 * execute control command 57 * - optionally send some data (command parameters) 58 * - optionally wait for the reply 59 * - optionally read some data from the reply 60 */ 61 static int cx82310_cmd(struct usbnet *dev, enum cx82310_cmd cmd, bool reply, 62 u8 *wdata, int wlen, u8 *rdata, int rlen) 63 { 64 int actual_len, retries, ret; 65 struct usb_device *udev = dev->udev; 66 u8 *buf = kzalloc(CMD_PACKET_SIZE, GFP_KERNEL); 67 68 if (!buf) 69 return -ENOMEM; 70 71 /* create command packet */ 72 buf[0] = cmd; 73 if (wdata) 74 memcpy(buf + 4, wdata, min_t(int, wlen, CMD_PACKET_SIZE - 4)); 75 76 /* send command packet */ 77 ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, CMD_EP), buf, 78 CMD_PACKET_SIZE, &actual_len, CMD_TIMEOUT); 79 if (ret < 0) { 80 if (cmd != CMD_GET_LINK_STATUS) 81 dev_err(&dev->udev->dev, "send command %#x: error %d\n", 82 cmd, ret); 83 goto end; 84 } 85 86 if (reply) { 87 /* wait for reply, retry if it's empty */ 88 for (retries = 0; retries < CMD_REPLY_RETRY; retries++) { 89 ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, CMD_EP), 90 buf, CMD_PACKET_SIZE, &actual_len, 91 CMD_TIMEOUT); 92 if (ret < 0) { 93 if (cmd != CMD_GET_LINK_STATUS) 94 dev_err(&dev->udev->dev, 95 "reply receive error %d\n", 96 ret); 97 goto end; 98 } 99 if (actual_len > 0) 100 break; 101 } 102 if (actual_len == 0) { 103 dev_err(&dev->udev->dev, "no reply to command %#x\n", 104 cmd); 105 ret = -EIO; 106 goto end; 107 } 108 if (buf[0] != cmd) { 109 dev_err(&dev->udev->dev, 110 "got reply to command %#x, expected: %#x\n", 111 buf[0], cmd); 112 ret = -EIO; 113 goto end; 114 } 115 if (buf[1] != STATUS_SUCCESS) { 116 dev_err(&dev->udev->dev, "command %#x failed: %#x\n", 117 cmd, buf[1]); 118 ret = -EIO; 119 goto end; 120 } 121 if (rdata) 122 memcpy(rdata, buf + 4, 123 min_t(int, rlen, CMD_PACKET_SIZE - 4)); 124 } 125 end: 126 kfree(buf); 127 return ret; 128 } 129 130 #define partial_len data[0] /* length of partial packet data */ 131 #define partial_rem data[1] /* remaining (missing) data length */ 132 #define partial_data data[2] /* partial packet data */ 133 134 static int cx82310_bind(struct usbnet *dev, struct usb_interface *intf) 135 { 136 int ret; 137 char buf[15]; 138 struct usb_device *udev = dev->udev; 139 u8 link[3]; 140 int timeout = 50; 141 142 /* avoid ADSL modems - continue only if iProduct is "USB NET CARD" */ 143 if (usb_string(udev, udev->descriptor.iProduct, buf, sizeof(buf)) > 0 144 && strcmp(buf, "USB NET CARD")) { 145 dev_info(&udev->dev, "ignoring: probably an ADSL modem\n"); 146 return -ENODEV; 147 } 148 149 ret = usbnet_get_endpoints(dev, intf); 150 if (ret) 151 return ret; 152 153 /* 154 * this must not include ethernet header as the device can send partial 155 * packets with no header (and sometimes even empty URBs) 156 */ 157 dev->net->hard_header_len = 0; 158 /* we can send at most 1514 bytes of data (+ 2-byte header) per URB */ 159 dev->hard_mtu = CX82310_MTU + 2; 160 /* we can receive URBs up to 4KB from the device */ 161 dev->rx_urb_size = 4096; 162 163 dev->partial_data = (unsigned long) kmalloc(dev->hard_mtu, GFP_KERNEL); 164 if (!dev->partial_data) 165 return -ENOMEM; 166 167 /* wait for firmware to become ready (indicated by the link being up) */ 168 while (--timeout) { 169 ret = cx82310_cmd(dev, CMD_GET_LINK_STATUS, true, NULL, 0, 170 link, sizeof(link)); 171 /* the command can time out during boot - it's not an error */ 172 if (!ret && link[0] == 1 && link[2] == 1) 173 break; 174 msleep(500); 175 } 176 if (!timeout) { 177 dev_err(&udev->dev, "firmware not ready in time\n"); 178 return -ETIMEDOUT; 179 } 180 181 /* enable ethernet mode (?) */ 182 ret = cx82310_cmd(dev, CMD_ETHERNET_MODE, true, "\x01", 1, NULL, 0); 183 if (ret) { 184 dev_err(&udev->dev, "unable to enable ethernet mode: %d\n", 185 ret); 186 goto err; 187 } 188 189 /* get the MAC address */ 190 ret = cx82310_cmd(dev, CMD_GET_MAC_ADDR, true, NULL, 0, 191 dev->net->dev_addr, ETH_ALEN); 192 if (ret) { 193 dev_err(&udev->dev, "unable to read MAC address: %d\n", ret); 194 goto err; 195 } 196 197 /* start (does not seem to have any effect?) */ 198 ret = cx82310_cmd(dev, CMD_START, false, NULL, 0, NULL, 0); 199 if (ret) 200 goto err; 201 202 return 0; 203 err: 204 kfree((void *)dev->partial_data); 205 return ret; 206 } 207 208 static void cx82310_unbind(struct usbnet *dev, struct usb_interface *intf) 209 { 210 kfree((void *)dev->partial_data); 211 } 212 213 /* 214 * RX is NOT easy - we can receive multiple packets per skb, each having 2-byte 215 * packet length at the beginning. 216 * The last packet might be incomplete (when it crosses the 4KB URB size), 217 * continuing in the next skb (without any headers). 218 * If a packet has odd length, there is one extra byte at the end (before next 219 * packet or at the end of the URB). 220 */ 221 static int cx82310_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 222 { 223 int len; 224 struct sk_buff *skb2; 225 226 /* 227 * If the last skb ended with an incomplete packet, this skb contains 228 * end of that packet at the beginning. 229 */ 230 if (dev->partial_rem) { 231 len = dev->partial_len + dev->partial_rem; 232 skb2 = alloc_skb(len, GFP_ATOMIC); 233 if (!skb2) 234 return 0; 235 skb_put(skb2, len); 236 memcpy(skb2->data, (void *)dev->partial_data, 237 dev->partial_len); 238 memcpy(skb2->data + dev->partial_len, skb->data, 239 dev->partial_rem); 240 usbnet_skb_return(dev, skb2); 241 skb_pull(skb, (dev->partial_rem + 1) & ~1); 242 dev->partial_rem = 0; 243 if (skb->len < 2) 244 return 1; 245 } 246 247 /* a skb can contain multiple packets */ 248 while (skb->len > 1) { 249 /* first two bytes are packet length */ 250 len = skb->data[0] | (skb->data[1] << 8); 251 skb_pull(skb, 2); 252 253 /* if last packet in the skb, let usbnet to process it */ 254 if (len == skb->len || len + 1 == skb->len) { 255 skb_trim(skb, len); 256 break; 257 } 258 259 if (len > CX82310_MTU) { 260 dev_err(&dev->udev->dev, "RX packet too long: %d B\n", 261 len); 262 return 0; 263 } 264 265 /* incomplete packet, save it for the next skb */ 266 if (len > skb->len) { 267 dev->partial_len = skb->len; 268 dev->partial_rem = len - skb->len; 269 memcpy((void *)dev->partial_data, skb->data, 270 dev->partial_len); 271 skb_pull(skb, skb->len); 272 break; 273 } 274 275 skb2 = alloc_skb(len, GFP_ATOMIC); 276 if (!skb2) 277 return 0; 278 skb_put(skb2, len); 279 memcpy(skb2->data, skb->data, len); 280 /* process the packet */ 281 usbnet_skb_return(dev, skb2); 282 283 skb_pull(skb, (len + 1) & ~1); 284 } 285 286 /* let usbnet process the last packet */ 287 return 1; 288 } 289 290 /* TX is easy, just add 2 bytes of length at the beginning */ 291 static struct sk_buff *cx82310_tx_fixup(struct usbnet *dev, struct sk_buff *skb, 292 gfp_t flags) 293 { 294 int len = skb->len; 295 296 if (skb_cow_head(skb, 2)) { 297 dev_kfree_skb_any(skb); 298 return NULL; 299 } 300 skb_push(skb, 2); 301 302 skb->data[0] = len; 303 skb->data[1] = len >> 8; 304 305 return skb; 306 } 307 308 309 static const struct driver_info cx82310_info = { 310 .description = "Conexant CX82310 USB ethernet", 311 .flags = FLAG_ETHER, 312 .bind = cx82310_bind, 313 .unbind = cx82310_unbind, 314 .rx_fixup = cx82310_rx_fixup, 315 .tx_fixup = cx82310_tx_fixup, 316 }; 317 318 #define USB_DEVICE_CLASS(vend, prod, cl, sc, pr) \ 319 .match_flags = USB_DEVICE_ID_MATCH_DEVICE | \ 320 USB_DEVICE_ID_MATCH_DEV_INFO, \ 321 .idVendor = (vend), \ 322 .idProduct = (prod), \ 323 .bDeviceClass = (cl), \ 324 .bDeviceSubClass = (sc), \ 325 .bDeviceProtocol = (pr) 326 327 static const struct usb_device_id products[] = { 328 { 329 USB_DEVICE_CLASS(0x0572, 0xcb01, 0xff, 0, 0), 330 .driver_info = (unsigned long) &cx82310_info 331 }, 332 { }, 333 }; 334 MODULE_DEVICE_TABLE(usb, products); 335 336 static struct usb_driver cx82310_driver = { 337 .name = "cx82310_eth", 338 .id_table = products, 339 .probe = usbnet_probe, 340 .disconnect = usbnet_disconnect, 341 .suspend = usbnet_suspend, 342 .resume = usbnet_resume, 343 .disable_hub_initiated_lpm = 1, 344 }; 345 346 module_usb_driver(cx82310_driver); 347 348 MODULE_AUTHOR("Ondrej Zary"); 349 MODULE_DESCRIPTION("Conexant CX82310-based ADSL router USB ethernet driver"); 350 MODULE_LICENSE("GPL"); 351